Automatic telephone system



July 13 1926. 1,592,682

w. w. OWEN AUTOMAT I C TELEPHONE SYSTEM Original Filed July 1. 1918 2 Sheets-Sheet 1 FlGr3 July 13 1926. 1,592,682

w. w. OWEN AUTOMATIC TELEPHONE SYSTEM Original Filed July 1, 1918 2 Sheets-Sheet 2 WWW (0W illu- Patented July 13, 1926.

UNITED STATES PATENT OFFICE.

WILLIAM WALTER OWEN, 0F OAK'PARK, ILLINOIS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO AUTOMATIC ELECTRIC INC., OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

AUTOMATIC TELEPHONE SYSTEM.

Application filed July 1, 1918, Serial No. 242,780. Renewed July 23 1824.

My invention relates in general'to that type of automatic telephone systems in which connections are extended between calling and called subscribers automatically, without the necessity of intervention by an operator.

Among the objects of my invention are to lessen the amount of equipment necessary to such a system, simplifying the operation thereof, and to so arrange the circuits and apparatus as to materially reduce the amount of operations necessary for a calling subscriber to establish a connection.

In the past it has been standard practice to use a plurality of automatic switches which were serially operated to extend a talking circuit, each switch having a caplacity of 100 trunks, that is, the switches ad access to ten levels or rows each containing ten trunk lines or sets of contacts. The calling device must therefore be operated once for all automatic selecting switches and twice for each connector, the calling device being of the ten impulse type, and when it is remembered that one operation is required in each case and sometimes two operations to-pick out one of 100 trunks, it will be seen that the operator must call a great number of digits on his calling device in a large exchange. It also has been the practice to add still more digits to a called number whenever that line is located in a branch exchange which requires more electing operations of the switches.

In my improved system I have so condensed the apparatus that the automatic selector switches which respond to one digit have each access to 300 trunk lines, while the connector switches which respond to two digits, have a capacity of 600 lines. In oper' ating these switches I still usethe same calling device mechanism of the ten impulse type, and the switches also are still of the ten step vertical and ten step rotary-type The difference being that a plurality of wipers are provided for each switch, one set for each hundred trunks, and the calling de vice has an improved controlling mechanism or finger hole dial which is so arranged that it automatically preselects the Wiper or set of wipers of a switch to be used on the forward rotation thereof, and on the backward rotation steps the switch to a certain point where the selected wipers may connect with stood by referring to the accompanying I drawings, in which Figures 1 and 2 illustrat-e-the switches required to extend a connection from one subscriber to another in a system of this type, the apparatus being shown in normal position.

Figure 3 shows a front view of the calling device to'be used in such a system, showing the front plate thereof and the arrangement of certain parts which cooperate with said dial on its forward movement to'preselect one of the wipers. The actual impulse send ing mechanism which is operated on the return movement of the dial to operate the line circuit a certain number of times is not shown but is well known to those familiar with the art. The finger hole dial has, as shown, three rows or sets of finger holes, the first row being designated by numbers, the second row by one set of letters, and the third row by another set of letters. If this dial is operated by inserting a finger in either the 1, A or L holes, the regular impulse springs will be operated to open the line circuit and step the switches one step in the usual manner upon the return movement of the dial. IIowever, a separate device including a movable finger lever which operates to round both sides of the line to pull up a differential relay in the successive switches is controlled by the forward move ment of the dial when controlled by any of the finger holes A to K, inclusive, to ground the line circuit twice, and grounds the line three times when the dial is controlled by any of the finger holes in the outer row L to X, inclusive. This grounding of the line circuit operates a differential relay or magnet in the various switches to connect the talking circuit of the switch to a certain one of the wipers of that switch in a manner to be pointed out.

Referring to Figure 3 the dial 91 is shown having three sets or rows of concentric finger holes. A finger stop 92 limits the movement of the dial. A movable finger lever 93 on the return movement.

draw it down to the stop 92. This movement of the lever 93 causes two of the teetlu on the arm 94, attached to the lever, to pass over the projection on the sprin 95 and force it into contact twice with t e spring 96. Then on the return movement of the 'dial when the finger is removed the teeth on -arm 94 pass under the projection on spring 95 and the line circuit is opened from one to ten times by the usual impulse mechanism. Now if the dial is o erated by inserting the finger into any of t e holes L to X, inclusive, the lever 93 will be drawn down farther so that the three teeth on arm 94 pass over the projection on spring 95. The springs 95 and 96 are shown connected in Fig. 1 and it will be seen that either two or three impulses from ground are delivered to both sides of the line circuit by these springs When the middle or outer row of finger holes are used.

Fig. 4 is a detail view showing certain parts of the calling device.

I will now describe the operations in detail when a subscriber such as A (Fig. 1) desires to call another subscriber (not shown). It being understood that the impulse springs C. D. (Fig. 1) are controlled in the usual manner by the return movement of the calling device (Fig. 3).

When the subscriber at A removes his receiver a circuit is closed for the line relay 2 of the line switch C from ground through the back contacts of relay 3 in series with the line circuit of substation A. Relay 2 closes a series circuit for relay 3 and magnet 4 through springs 5, and prepares a direct circuit for the magnet 4 at sprin s 6 extending to the private wiper 9. his switch is of the type which stands upon the trunk line last used and if this trunk line is now busy a ground will be present at the private contact thereof which will cause the magnet 4 to energize over the direct circuit previously traced to step the wipers 7, 8 and 9 to the contacts of the next trunk line. This ground short circuits the relay 3 in the series circuit so that said relay does not energize. The magnet 4 continues to oper ate in the manner of a buzzer as long as busy trunks are found to rotate the wipers onto the first idle trunk line; at which time, there being no ground on wiper 9, relay 3 will no longer be shorted out and will energize to disconnect relay 2 and ground from the line circuit and switch the same to the wipers 7 and 8. Relay 3 being of comparatively high resistance does not permit magnet 4 to energize over the series circuit. Relay 3 also prepares a locking circuit for itself at springs 10 which will later be completed from the switch ahead;

As soon as relay 3 energizes a circuit is closed for the line relay 11 of the seized switch E in series with a special difierential relay 12 and the line circuit of substation A. The switch is now ready to respond to the first digit of the called number, which determines in which sub-division of the system the line is located and also in which part of that sub-division. That is the switch E has three sets of line and private banks and a wiper for each, each linebank containing one hundred sets of contacts connected to 100 trunk lines leading to one subdivision. It, therefore, the called line is in the first subdivision, the lower set of line wipers must he used to connect with a trunk in the lower bank, and the second wipers and bank if the line is in the second group, and so on. Assume that the called line is in that subdivision to which the trunks in the lower bank lead and is in the first group or lower level of that bank, then the first digit will be 1 and the subscriber will insert a finger into the number 1 hole tooperate the calling device. In this case the springs C. D. are operated in the usual. manner to open and close the line circuit-once. Relay 12 does not energize in the series circuit with relay 11. being differential, but relay 11 does energize and closes a circuit for re lay 13 which connects ground to the holding circuit of relay 3 of switch C and makes switch E busy, also preparing a circuit for vertical magnet 14 and series slow relay 15. Now as relay 11 falls back in response to the first digit the circuit of magnet 14 and relay 15 is closed and the wipers 16 to 24, inclusive, are raised one step from normal by magnet 14 in position before the first level of trunks and the 0H normal springs 25 and 26 close contact. Relay 15, upon energizing, closes a circuit for relay 2? through springs 28, 29, 30 and 26, and relay 27 prepares a circuit for the rotary magnet 31 at springs 32, and closes a locking circuit for itself at springs 33 through springs 34 of the rotary magnet. As soon as relay 15 falls back the circuit of magnet 31 is completed at springs 29 and 35 and the wipers 16-24 are rotated one step onto the first set of contacts in the lower levels of their respective hanks. This switch E is provided with a small rotary auxiliary switch having three wipers 36, 37 and 38 which may be operated over three sets of contacts leading to the line and private wipers by a rotary magnet 39 which is in turn controlled by. relay 12. The wipers if operated are released when the switch itself releases by the operation of the release magnet 40. In the case of the call being described, relay 12 Was not operated and therefore wipers 36, 37 and 38 rest in the1r normal position with the trunk circuit connected to wipers 16, 17 and 18. As the wipers rotate in response to the operation of rotary magnet 31, therefore, only the pnvate wiper 18 is effective to test trunks and an idle trunk line in the first level of the lower bank will be selected in the usual manner by the alternate operation of relay 27 and magnet 31. As soon as such idle trunk is reached, relay 41 which has heretofore been short circulted by the ground on wiper 18. energizes over a circuit from ground through springs 28, relay 41, springs 34, and relay 27 to battery, relay 27 being of comparatively low resistance does not energize at this ,time and the relays of switch E are disconnected by relay 41 from the line circuit, which is extended through springs 42 and 43 and wipers 36 and 37 to the line wipers 16 and 17 and thence to the line relay of a selected connector switch such as H (Fig. 2). Relay 41 also opens one point at springs 44 in the circuit of the release magnet and closes a locking circuit for itself at springs 45 to the private wiper 18 which is supplied with ground from the switch ahead.

'As soonas the line circuit is cut through line relay 46 of switch H (Fig. 2) energizes in series with the extended line circuit and relay 47, which rela 47 is the same as relay 12 of selector E and being differential, does not energize at this time. The connector switch H is also provided with a small rotary auxiliary switch similar to that of switch E except that the wipers 48, 49 and 50 of this switch have a bank of seven sets of contacts over which they may be rotated by a magnet 51. One of the seven sets of contacts is dead but the other six sets are each connected to one of six sets of line and private wipers of the switch H. Line relay 46 closes a circuit for nelay 52 which closes the holding circuit of the relay 41 at springs 53 and prepares the circuit of the vertical magnet 55 and slow series relay 56 at springs 54. This switch H has access to 6 banks of 100 lines each and the calling subscriber must therefore operate the magnet 51 either two, three, four, five or six steps to connect the trunk circuit to one of the sets of wipers which has access to that 100 lines in which the called line is located so that when the switch and all of its wipers are operated up and in only that set of wipers will be effective to extend a connection which has been connected with by the operation of magnet 51. If the called line is located in the first or lower bank then the last two digits of the called number will be 1-1 or 1-2 or 3.-5, etc., depending 56 and magnet 55, magnet 55 operating to step all of the wipers 57 to 74 inclusive, ope posite the first level. of their respective banks. Off normal springs 75 and 76 are closed at this time and springs 77 are opened so that the circuit of relay 56 and magnet 55 extends through springs 76 and front contacts of relay 56. As relay 56 falls back after the first digit it prepares a circuit at springs 78 for rotary magnet 79 and slow relay 80. As the relay 46 is operated by the next digit it closes the circuit of relay 80 and magnet 79 in multiple. Magnet 79 operates to step the wipers 57 to 74 inclusive, onto the first set of contacts in their respective banks. As the wipers 48, 49 and 50 still stand in normal position only the wipers 57, 58 and 59 are effective and the testing will be performed over only the private wiper 59. Relay 80 holds the busy relay .81 connected to wiper 59 for a second after this digit and if the line is busy relay 81 pulls up from ground on said wiper to give a busy signal and lock the switch until released. If the line is not busy, then as soon as relay 8O falls back the circuit of relay 82 is closed. Relay 82 will now energize over a. circuit from ground through springs 53, springs 83, upper winding of relay 82, springs 84, wiper 50, wiper 59, and through the bridge cut off relay of the called line to battery. The energization of relay 82 connects the called line to the ringing circuit from wiper 58 through wiper 49, springs 85, springs86, to ringing interrupter R and the other side from wiper 57, through wiper 48, springs 87, springs 88, and through one winding of ring cut off relay 89 to battery. As soon as the called subscriber answers, relay 89 energizes to disconnect the ringing circuit and substitute the back bridge relay 9 0, whereupon conversation may proceed in the usual manner.

Should the calling subscriber desire to call some party whose line is accessible to connectors which are in the second bank of the selector E then the called number would be A11 or B1--1, etc., the particular letter A to K used depending upon the subgroup of connectors or level in which the said connector is connected with. In this case as the first digit is sent by using the middle row of finger holes on the calling device, then the springs and 96 will be operated twice before the switch begins to 'move, this grounding of the line circuit short circuits one winding of relays 12 and 11 of selector E, causing relay 12 to energize without affecting relay 11. Relay 12, upon energizing, sends 2 impulses to the rotary magnet 39 which operates to step the wipers 36,

37 and 38 onto the contacts leadin to the line and private wipers 19, 20 an 21, so that in this case after the wipersare raised to some level and cut in, an idle trunk in the desired level of the second bank will be selected by means of the private wiper 21 which is now effective.

In the same manner, if the line is in the third subdivision of the exchange, then the first digit of the called number would be one of the letters L to X, inclusive, and in this case springs 95 and 96 being operated three times would step the wipers 36, 37 and 38 to the fourth set of contacts leading to the line and private wipers 22, 23 and 24 and an idle trunk in the third bank will be selected.

Now, it will be seen that after the calling man has picked out the desired one of three subdivisions and an idle connector in the group of that subdivision he may then pick out any one of six groups of 100 lines each from the connector. It has already been explained how a connection is extended to a line in the first hundred (or lower bank). Now if the called line is in the second bank or hundred of the connector then the last two digits will be A1 or B2, etc. depending on the location of the line in that hundred. When the digit A is called the springs 95 and 96 will be operated twice and will in this case operate the differential relay 47 of the connector to cause the rotary magnet 51, of the auxiliary switch to step the wipers 48, 49 and 50 onto the third set of contacts leading to the line and private wipers 60, 61 and. 62 so that as the dial returns and is then operated for the last digit a connection will be extended only over the wipers 60, 61 and 62 to some line in the second bank.

If then a line located in the third bank is wanted then the last two digits will be L--1 or M2, etc, so that the first digit to the connector willbe sent by using the outer row of holes of the dial. In this case springs 95 and 96 will be closed three times and through relay 47 and magnet 51 will step the wipers 48, 49 and 50 onto the contacts leading to line and private wipers 63, 64 and 65.

If the called line is located in the fourth bank then the last two digits will be AB or AA, etc., so that both digits to the connector will be sent on the middle row of holes. In this case the relay 47 will be operated twice before the vertical movement of the switch and twice before the rotary movement, so that the magnet 51 is operated four times and connects the trunk circuit to the wipers 66, 67 and 68.

It the line is located in the fifth bank then the last two digits will be AL or B-M, etc, and the magnet 51 will operate five times to step the wipers 48, 49 and 50 five steps to connect the trunk circuit to the line and private wipers 69, 70.and 71. And it the line is in the sixth hundred or upper bank then the last two digits will be LL or LM, etc. and in this case magnet 51 operates six times to connect the trunk circuit with the line and private wipers 72, 73 and 74. Thus it will be seen that the talking subscriber on the forward movement of the dial, preselects the group or division of the exchange by selecting a pair of wipers in the selector and that on the forward movement of the dial for the last two digts, a group from the connector is preselected by picking out a set of wipers in said connector.

It will he understood that the magnet 51 may be dispensed with and that relay 47 may be used to directly operate the wipers 48, 49 and 50, and also the relay 41 of the selector may directly operate the wipers 36, 37 and 38. Also it will be understood that the wipers 36, 37 and 38 and the wipers 43, 49 and 50 are held in their advanced position by any pawl or ratchet arrangement, which is releasedwhen the release magnets oi the respective switches energize.

Therefore it will be seen that I have provided a very efficient method of calling in an automatic system so that a less number of digits will take care of calls and so that the switches themselves will be decreased in number,

Having fully described and ascertained the features and method of operation of my invention, what I consider to be new and desire to have protected by Letters Patent will be pointed out in the appended claims.

What I claim as my invention is:

1. In a telephone system. a calling de vice for sending impulses of current to operate automatic switches having a dial. means operated by the movement of the dial in one direction for sending a variable number of impulses and means operated by the movement of the dial in another direction for also sending a variable number of impulses, .said first means comprising a movable finger lever operated when the dial is rotated forward to send two or more impulses, and said second means comprising mechanism operated by the dial on its return movement for sending two or more impulses.

2. In a telephone system, a calling device for sending impulses of current to operate automatic switches, a dial for controlling said device. means operated by the movement of the dial in one direction for sending a variable number of impulses and means operated by the movement of the dial in another direction for also sending a va riable number of. impulses, a line circuit arranged to be controlled by said calling device, said first means adapted to connect and said second means adapted to open and close a circuit including the two sides of said. line circuit in series.

3. In a telephone system, a calling device for sending impulses of current to operate automatic switches, a dial for controlling said device, means operated by the movement of the dial in one direction for sending a variable number of impulses, means operated by the movement of the dial in another directionfor also sending a variable number of impulses, said dial having a plurality of rows of finger holes, said first means comprising a finger lever which is operated in one manner to send a plurality of impulses when the device is controlled through the medium of one row of holes and which is operated in another manner to send a different number of impulses when the device is controlled through the medium of another set of holes.

4. In a telephone system, a calling device for sending impulses of current to operate automatic switches, having a dial, means operated by the movement of the dial in one direction for sending a variable number of impulses, means operated by the movement of the dial in another direction for also sending a variable number of impulses, an automatic switch associated with said calling device having a plurality of wiper sets, and an auxiliary switch for selecting a set of wipers, said auxiliary switch responsive to the impulses sent by said calling device when moved in one direction to select a set of wipers ands-aid automatic switch responsive to the impulses sent by the calling device when moving in the other direction to move said wipers.

5. In a telephone system, a calling device for sending impulses of current to operate automatic switches, a dial for controlling said device, means operated by the movement of the dial in one direction for sending a variable number of impulses, means operated by the movement of the dial in another direction for also sending a variable number of impulses, said dial having a plurality of rows of finger holes, said first means comprising a finger lever which is operated in one manner to send a plurality'of impulses when the device is controlled throu h the medium of one row of holes and w ich is operated in another manner to send a diflerent number of impulses when the device is controlled-through the medium of another set of holes, an automatic switch associated with said calling device having a plurality of wiper sets, and an auxiliary switch for selecting a set of wipers, said auxiliary switch responsive to the impulses sent b said calling device when moved in one irection to select a set of wipers and said automatic switch responsive to the impulses sent by the calling device when movingin the other direction to move said wipers.

6. In a telephone system, an automati switch, a line circuit leading thereto, a plurality of wiper sets for said switch, stepby-step mechanical means for selecting any one of said sets of wipers, means for moving said wipers, a circuit including only one side of said line circuit for operating said wiper selecting means, and a circuit including the two sides of said line circuit in series for operating said last means to move the wipers.

7. In a telephone system, an automatic switch, a lurality of sets of wipers therefor, a di erential line relay therefor, an auxiliary step-by-step wiper selecting switch controlled thereby, and a line circuit over which said differential relay is controlled to operate said auxiliary switch to extend a connection toward a called subscriber by selecting a particular set of wipers, and a second line relay in combination with said first line. relay, said two relays operated alternately to extend said connection.

8. In a telephone system, an automatic switch having a pair of line relays in combination with a calling device for sending successive series of impulses, a plurality of sets of wipers for said switch, one line relay responsive to only one series of impulses to select a set of wipers and the. other responsive only to another series of said impulses.

9. In a telephone system, an automatic switch having a pair of line relays in combination with a calling device for sending successive series of impulses, a plurality of sets of wipers for said switch, one line relay responsive to only one series of impulses to select a set of said wipers and the other responsive onl to another series of said impulses, the switch operated in a progressive manner in response to each line relay.

10. In a telephone system, an automatic switch, a line circuit leading thereto, a plurality of wiper sets for said switch,- means for selecting any one of said sets of wipers, means for moving said wipers, a circuit including only one side of said line circuit for operatin said wiper selecting means, and a circuit including the two sides of said line circuit in series for operatin said last means to move the wipers, sai wiper selecting means comprising an auxiliar progressively movable switch, a calling evice, said calling device having mechanism for first controlling said circuit over one side of the line circuit to operate the auxiliary switch and for then controllin circuit over the two sides of the line circuit in series to move the wipers.

11. In a telephone system, an automatic switch, a line circuit leading thereto, a plurality of wiper sets for said switch stepthe - by-ste mechanical means for selecting any one 0 said sets of wipers, means for moving said wipers, a circuit including only one side of said line circuit for operating said wiper selecting means, and a circuit including the two sides of said line circuit in series for operating said last means to move the wipers, a calling device associated with said automatic switch, having mechanism for controlling both of said circuits, said first means including a line relay responsive only to im ulses over said first circuit and said secon' means including a line relay responsive only to impulses over the second circuit.

12. In a telephone system, an automatic switch, a line circuit leading thereto, a

lurality of wiper sets for the switch, means or selecting a set of said wipers, means for moving the wipers, a calling device associated with the line circuit and having mechanism for first sending different codes of impulses over the line circuit to operate said first means to select different sets of wipers and for then sending different codes of impulses over theline circuit to operate said second means to move the wipers, in response to a single manual operation of the calling device.

13. In a telephone system, an automatic switch having a plurality of sets of wipers, a calling device associated therewith having means for sending a series of impulses on its forward movement to select a set of wipers for use and for sending one or more impulses on its backward movement to move said wipers.

14. In a telephone system, an automatic switch having a plurality of sets of wi ers and an auxiliary wiper selecting switc a calling device associated with said switch having means for sending variable series of impulses on its forward movement to 0 erate said auxiliary switch and for sen g impulses on the backward movement for moving said wipers.

15. In a telephone system, a calling device for sending impulses of current to operate automatic switches, a dial for said device operated manually in one direction for sending a plurality of impulses and automatically operated in a reverse direction for sending either a single impulse or a variable number off impulses.

16. In a telephone system, a calling device operable in accordance with the digits of called numbers to operate automatic switches, said device having a dial rotated forward and backward once for each digit of the number called, and means controlled by the operation of the device for each digit for transmitting a series ofimpulses on the forward rotation and another series of impulses on the backward rotation.

11'. In a telephone system, a calling device, an automatic switch having a plurality of sets of wipers, an auxiliary switch associated therewith, said calling device 0perated in accordance with each digit of a called number to transmit a series of impulses, said auxiliary switch operated in response to more than one of said series of impulses to move in a single plane to select a set of wipers.

18. In a telephone system, a calling device for sending impulses of current to operate automatic switches, a dial for said device manuall means or returning said dial to normal when released, mechanism controlled by said dial for transmitting a series of impulses when the dial is rotated away from normal position, and mechanism for sending a second series of impulses when the dial returns to normal position.

19. In a telephone system, a calling device for sending impulses of current to rotatable from a normal position,

operate automatic switches, a dial for said -vice having a finger hole dial, a plurality of rows 0 finger holes on said dial, said device operable through the medium of a finger hole in any row, means operated by the movement of the dial in one direction for sending two or more impulses, the number dependent upon the row of holes used, and means operated by the movement of the dial in another direction for sending two or more impulses.

21. In a telephone system, a calling device having a finger hole dial, a finger lever for said device, said device having means operable through the medium of said dial to transmit a plurality of impulses, and means controlled by said finger lever for transmitting a plurality of impulses each time the dial is operated.

22. In a telephone system, a calling device, a finger hole dial therefor having a plurality of rows of finger holes, a fin er lever for said device having means Ior transmitting im ulses, said device operated through the me ium of a finger hole in certain of said rows, said lever operated in a variable manner, dependent upon the row of holes used to operate the dial, to transmit two or more impulses.

23. In a telephone system, a pair of automatic switches each having an operating magnet, a calling device having means for transmitting impulses on both its forward and backward movement, and circuit connections whereby the impulses transmitted on the forward movement operate one of said switches and the impulses transmitted on the backward movement operate the other of said switches.

24. In a calling device for a two-Wire telephone system, an impulse transmitter, a rotary member controlling said impulse transmitter, and means whereby said im pulse transmitter sends a series of impulses during its forward rotation and whereby said impulse t'ansniitter sends a series of impulses during its backward rotation.

25. In an impulse transmitter, a plurality of independently movable commutators for transmitting various series of impulses, and means for operating one of said commutators and subsequently operating another commutator.

26. In an impulse transmitter, a plurality of independently movable commutators for transmitting various series of impulses, and means for selectively operating one of said commutator-s and subsequently operating another commutator.

Signed by me at Chicago, Cook County, Illinois, this 22d day of June, 1918.

IVILLIAM WALTER OWEN 

